1. Field of the Invention
This invention is related to control of the types and amounts of fatty acids present in plant tissues and is particularly related to methods for increasing the percentage of fatty acids containing sixteen or fewer carbon atoms, preferably 14 or fewer.
2. Description of the Background
Fatty acids are ubiquitous in living forms, providing glycerides essential to membrane formation, as precursors to a wide variety of products, and as stored energy. The most abundant fatty acids tend to be the longer chain fatty acids, such as palmitate (C16:0) and stearate (C18:0). These higher fatty acids lack the many desirable properties of the shorter chain fatty acids in the range of about 8 to 12 carbon atoms, and even C14 carbon chain, which have lower melting points and can find use in a variety of applications in food, specialty oils, paints, lubricants, detergents, and the like. Fatty acids containing 8 to 14 carbon atoms are considered "medium chain fatty acids."
For the most part, animal fats tend to be longer chains (e.g., 16:0, 18:0). Traditionally, the commercial source of oils high in medium chain fatty acids are coconut oil and palm kernel oil. Both of these products are grown only in tropical climates and are subject to wide annual variations in cost and availability. Alternative sources of medium chain fatty acids are needed.
The fatty acids are synthesized in plants in the chloroplast, proplastid, or related organelles. It is therefore of interest to be able to selectively modify the chloroplast fatty acid synthesizing system to change the fatty acid composition and distribution to produce fatty acid compositions which are different from the fatty acid composition normally produced by the particular species.